KLAC first signed on in 1924 as KFPG. In 1925, it became KMTR, with the call sign chosen for the new owner, K. M. TuRner, a radio dealer. In the 1930s, it was powered at 1,000 watts and had its studios at 915 North Formosa Street.[3]

In 1946, Dorothy Schiff, publisher of the New York Post, bought the station and renamed it KLAC, for Los Angeles, California. During the 1940s, Douglas Adamson worked as a disc jockey on KLAC and was voted one of Billboard magazine's top ten DJs in America. Al Jarvis created his West Coast version of the "Make Believe Ballroom." In a KLAC advertisement in the 1947 edition of Broadcasting Yearbook, Jarvis is described as "the dean of the nation's disc jockeys." The show promised to give away "a new Mercury, diamond rings, etc."[4]

In 1948, KLAC added a TV station, Channel 13.[5] KLAC-TV signed on the air on September 17. Both the radio and TV operations were housed in studios at 1000 North Cahuenga Boulevard in Hollywood. Al Jarvis hosted a TV edition of the "Make Believe Ballroom." A young Betty White was one of his staff, with Regis Philbin and Leonard Nimoy also working behind the scenes at Channel 13. KLAC-TV was sold to the Copley Press in 1953, with the call letters changed to the current KCOP-TV.

Also in 1948, KLAC-FM began experimenting with FM broadcasts. The station official signed on the air on March 7, 1961, as KLAC-FM.[6] It mostly simulcast the AM station. In the late 1960s, it began airing its own programming, a vocal easy listening/MOR sound. In 1975, the station was sold to Combined Communication, later becoming KIIS-FM.

In the mid-1960s, KLAC switched to a talk radio format known as "Two-Way Radio." Hosts included Joe Pyne. In the 1970s, KLAC switched to an adult standards sound, playing music from the 1940s and early 1950s, along with soft adult contemporary hits of the 1950s and 1960s. By early 1970, KLAC evolved to more of a full service mainstream adult contemporary format focusing on popular adult hits from 1964 up to that time.

As the 1970s began, Los Angeles had two country music stations, 1280 KFOX and 870 KIEV.[8] But neither station had a signal as powerful as that of KLAC. So on September 28, 1970, KLAC decided to drop adult contemporary for country music. The number one on the station's first "Big 57 Survey" was "For The Good Times" by Ray Price.

The original DJs included Deano Day, Gene Price, Harry Newman, Sammy Jackson and Jay Lawrence, joined the following year by Dick Haynes, Charlie O'Donnell and Larry Scott. L.A. veteran DJ Nancy Plum (KTNQ, KMPC) was heard in the last days of the country format.

In the fall of 1980, KLAC got some serious competition in the country music field, including a station on FM. KZLA FM 93.9 and AM 1540 switched to country, followed in December 1980 by AM 930KHJ. KHJ returned oldies on April 1, 1983. KZLA-AM-FM and KLAC competed through the 1980s. During this time, KLAC DJ Harry Newman could also be heard as the image voice for Channel 13 KCOP-TV, which had been co-owned with KLAC until the late 1950s. (KCOP later became a sister station to Channel 11 KTTV, which previously was co-owned with KLAC for 21 years.)

KLAC was owned by Malrite until 1993, when the station was sold to Shamrock Communications in a group deal along with KZLA. In 1995, Shamrock's stations were absorbed by Chancellor Media and KZLA was swapped to Bonneville International in the late 1990s. Chancellor Media became AMFM Inc. when it merged with Capstar in 1999. In 2000, AMFM Inc. merged with Clear Channel Communications. In 2016, Clear Channel changed its name to iHeartMedia, KLAC's current co-owner.

On February 4, 2005, Clear Channel Communications made a format swap on three radio stations in Southern California.

KLAC's previous standards format, and "Fabulous" branding, moved to XETRA690 AM, a border blaster station in Tijuana and heard around Southern California. It became The Fabulous 690. This lasted until February 1, 2006. With an ownership change and ending of Clear Channel's programming lease, 690 AM became XEWW, a Spanish-language talk station.

The XTRA Sports format, previously simulcast on XETRA 690 AM in San Diego and KXTA1150 AM in Los Angeles, moved to KLAC, which initially aimed at both Los Angeles and San Diego. (Prior to 2002, 690 and 1150 were separately programmed stations, with the only common programming being The Jim Rome Show.)

When 690 and 1150 were merged on 570, Jim Rome and sportscasters Steve Hartman, Lee Hamilton and Vic "The Brick" Jacobs were retained. The other hosts from 690 and 1150 went on to other stations. Several former XTRA Sports 690 hosts joined the upstart sports format at San Diego-based 1090 XEPRS-AM, known as "The Mighty 1090."

In February 2006, KLAC phased out the use of the XTRA Sports nickname as part of a re-orientation to the Los Angeles market, and was simply referred to on air as "AM 570." The XTRA Sports name was later re-launched in San Diego on AM 1350 KLSD on November 12, 2007, with Lee Hamilton starting local programming.

For a brief time, AM 570 placed less emphasis on sports and more emphasis on male-oriented talk to compete with the now-defunct 97.1 KLSX, then the local home of Adam Carolla and Tom Leykis, and previously Howard Stern's L.A. station. Local hosts on KLAC were instructed to not limit themselves to sports, but also include celebrities, relationships, politics and current events. In addition, non-sports hosts Erich "Mancow" Muller and Phil Hendrie were added to the lineup.

The switch also meant that former afternoon host and one-time San Diego Chargers radio voice Lee "Hacksaw" Hamilton was moved to weekend duty. He also hosted a daily 5 p.m. sports update on KLAC for several months until landing a weekday show on San Diego-based sister station 1350 KLSD.

The KLAC call letters were initially only announced during station identification at the beginning of each hour. But they soon started to be used more often under the "AM 570 KLAC" brand, starting when the station celebrated its 30th anniversary as the Laker radio flagship. Some promotions spelled out the meaning of the call letters as K Los Angeles California.

Starting in late 2006, KLAC shifted its focus again to more sports content. Phil Hendrie voluntarily retired from his syndicated show to pursue an acting career (but would later revive the program on KTLK). Hendrie's time slot was filled by Joe McDonnell, who would last for two years at KLAC. Into The Night with Tony Bruno, which KLAC co-produced with The Content Factory, replaced McDonnell in September 2008.

Mancow was replaced with Roggin and Simers2(Squared), hosted by Fred Roggin of Channel 4 KNBC (and formerly of one-time rival sports talker 710 KMPC), T.J. Simers of the Los Angeles Times, and Simers' daughter, Tracy Simers. Roggin and Simers2 lasted 11 months before being replaced in September 2007 by Dan Patrick's syndicated morning show, also produced by The Content Factory.

On December 11, 2008, the Los Angeles Lakers announced that KLAC would no longer be the team's flagship station following the 2008-2009 season, with Laker games moving to AM 710KSPN, ESPN Radio's Los Angeles station.[9]

On January 20, 2009, the station announced a merger with the Fox Sports Radio Network. Many of the network shows would be based at KLAC, with the end of most local programming. General manager Don Martin was named KLAC's program director. Martin also became the network's program director, replacing Andrew Ashwood, who died a few months earlier.

Shemon and Washington's morning slot was replaced by Dan Patrick's syndicated morning show, while Chris Myers' and Hartman's midday shows combined into one, "Myers and Hartman." Myers replaced Mychal Thompson (who was expected to leave the station at the end of the Laker season). Vic "The Brick" Jacobs was reassigned to delivering brief sports updates. Siciliano and Fernandez's early evening show was replaced by the "Petros and Money Show." Petros and Money were carried on Fox Sports Radio Network between 2009 and 2014.

KLAC initially dropped "Into The Night with Tony Bruno," clearing JT The Brick instead. Ben Maller's overnight show, The Third Shift, was canceled and replaced by a clip show entitled Fox Sports Soup. JT The Brick's show replaced Fox Sports Soup later in the year as the network assumed production of Into The Night and rehired Maller for weekend duty.

Myers left "Myers and Hartman" in March 2010 to focus on his other duties with Fox Sports, replaced by Pat O'Brien as co-host of the resurrected "Loose Cannons" show, alongside Hartman and Jacobs.

In September 2014, the Dodgers announced the team would buy an equity stake in KLAC, co-owning the station with iHeartMedia.[11] The Dodgers wanted to be the principal sports franchise carried on the station, with advertising imaged around the team. Dodgers President Stan Kasten said “We will be teaming up with the fantastic creative team at iHeartMedia on a number of projects and initiatives, to enhance our fans engagement."

On March 15, 2015, KLAC announced that it would drop its branding connected with Fox Sports Radio, changing to "AM 570 LA Sports," with a greater emphasis on Dodgers coverage, including a weeknight "Dodgers Talk" show all year round. The "LA" in KLAC's logo is derived from the Dodgers' cap insignia. Never the less, KLAC continued to carry some of the Fox Sports lineup such as Dan Patrick's morning show and Jay Mohr's midday show. The change in ownership was consummated on August 5, 2016.

On March 16, 2016, KLAC announced it would take over as the flagship station of the Los Angeles Clippers. In case of a scheduling conflict with the Dodgers, the Clippers would be heard on sister station 1150 KEIB.[12]

In 2017, KLAC and its sister station 640 KFI acquired the rights to the Los Angeles Chargers. The play by play would air on KFI, with team shows and special programming on KLAC.[13]